Coating Defects Flashcards
1
Q
Inspectors should consult with the manufacturer’s ___ ____ about coating failures whenever possible.
A
Tech Rep
2
Q
Nondrying Film (Failure to cure) is a common problem on many projects, frequently caused by not adding the 1___ to the ___, adding the 2___ ___ or not adding the 3___ ___ of ___.
It is vitally important to the success of the project that the inspector observe during mixing.
A
- Not adding cure to the base.
- Adding the wrong cure.
- Not adding the correct amount of cure.
3
Q
Nondrying cure may also be caused by an issue with the coating itself. A quick check with the manufacturer using the ___ ___ might have a quick answer.
A
Batch Number.
4
Q
Nondrying/failure to cure defect causes could be:
- Environmental conditions: ___ ___, ___ or ___ conditions
- ___ or ___ thinner.
- ___ in some generic thinners can react with the cure.
- Not adding ___ to the base. Or adding the ___ ___ or ___ ___.
A
- Too hot, cold or humid conditions.
- Wrong/contaminated thinner.
- Moisture in some generic thinners can react with the cure.
- Not adding cure to the base. Or adding the wrong types or wrong amounts.
5
Q
(Based upon Photo) A non cured coating seems to look like a tar, similar to tobacco tar with about the same consistency.
A
Note.
6
Q
(Based upon Photo) Amine blush looks like dried milk on the surface.
A
Note.
7
Q
If cured during conditions of cool ambient temps, dropping temps, or high humidity ___ ___ ___ ___ coatings can develop a surface oiliness or exudate. Commonly referred to as Amine Blush or Amine Sweating.
A
Amine Cured Epoxy Resin Coatings.
8
Q
If cured during conditions of cool ambient temps, dropping temps, or high humidity amine cured epoxy resin coatings can develop a ___ ___ or ___. Commonly referred to as Amine Blush or Amine Sweating.
A
Surface oiliness or exudate.
9
Q
Exudate is a ___ ___.
A
Secreted Substance.
10
Q
Amine Blush/Sweating is caused by the absorption of ___ ___ and ___ into the coating film and it’s reaction with amine curing.
A
Carbon dioxide and water.
11
Q
Causes of Amine Blush/Sweating are:
- Too ___ or ___ temps during curing.
- High ___ during curing.
- A drop in ___ during coating.
A
- Too hot or cold temps during curing.
- High humidity during curing.
- A drop in temp during coating.
12
Q
Some of the problems with amine blush/sweating can be:
- Surface ___ or ___.
- Incomplete ___.
- Poor ___.
- Poor ___ on ___ ___.
- Coating ___ over time.
- Poor ___ retention.
A
- Surface tackiness or greasiness.
- Incomplete cure.
- Poor adhesion.
- Poor adhesion on over coating.
- Coating discoloration over time.
- Poor gloss retention.
13
Q
The best method to fix amine blush is to 1?
- If amine blush does occur the CI should consult with the ___ ___ and the ___ ___ prior to making any recommendation regarding the attempt to repair/over coat it.
A
- Avoid it by adhering to strict environmental controls. (This is not a fix, you morons. This is prevention.)
- Coating manufacturer and the project engineer.
14
Q
There are a number of kits on the market to detect amine blush.
A
Just a note.
If the kits can detect it, doesn’t that mean it’s already happening and the kit is just letting you know a short period of time before it’s visible? What good is that?
15
Q
Runs, sags, curtains or wrinkles may be caused or worsened by:
- Applying the coating ___ ___.
- Using too much, or the wrong, ___.
- Surface is ___ ___ to apply the coating.
- Applying the coating at the end of its ___ ___.
- Wrong thixotrope used in ___.
- Improper ___ ___.
A
- Applying the coating too thickly.
- Using too much, or the wrong, thinner.
- Surface is too hot to apply the coating.
- Applying the coating at the end of its pot life.
- Wrong thixotrope used in manufacturing.
- Improper spray technique.
16
Q
The first step to addressing a run or drip is to see if the applicator can fix it right away by 1___ or ___ the coating with a 2. ___ or ___.
If the run or drip is already hard, report the issue to the owner.
A
- Lifting or Spreading.
2. Brush or roller.
17
Q
In some cases a run or sag is acceptable. Otherwise, ensure the crew ___ it ___ and ___ the new material at the ___ ___, based on the specification and manufacturers’ recommendation for repairs.
A
Sands it down and applies the new material at the correct thickness,
18
Q
(According to photo) runs looks like half melted coating, or a puddle of coating.
A
Just a note.
19
Q
Discontinuities, skips, holidays and missed areas:
These defect are 1___ ___ of the substrate or previous coating caused by:
- Poor ___ ___,
- Lack of a ___ ___.
- Lack of ___
- Poor ___
A
- Exposed Areas
- Poor application technique.
- Lack of a stripe coat.
- Lack of Inspection.
- Poor Inspection.
20
Q
Discontinuities, skips, holidays and missed areas:
Base the repair on the 1___. If there is no recommended repair procedures, then leave the method up to the 2____ ___.
- Ensure the ___ gives ___ before making the repair.
A
- Specification.
- Manufacturers recommendations.
- Owners gives approval.
21
Q
Chalking is a powdery, friable layer on the surface of a coating normally cause by 1___ to ___ ___.
It can also be due to exposure to other forms of 2 ____ including ___ ___.
A
- Exposure to UV Light.
2. Radiation. Including nuclear radiation.
22
Q
The UV Light or radiation break down the bond 1___ ___ in the coating film. It is most common in 2___ films but can be seen in almost all coatings left to exposure to causative conditions.
A
- Between Molecules.
2. Epoxy
23
Q
To overcoat Chalking:
- Remove the powdery later by ___ or ___ ___ to a point acceptable to the project owner.
A
Sanding or pressure washing.
24
Q
ASTM D4214-07 is the?
A
Standard test methods for evaluating the degree of chalking of exterior paint films.
25
(According to Photo) Cratering is pretty. It looks like small indentations with raised edges. Similar to what you would expect on the surfae of the moon.
Just a note.
26
Cratering is the formation of a small bowl-shaped depression in the coating caused by ___ trapped in the coating. It can also be caused by 2___ ___ __.
Air.
2. Improper mixing procedures.
27
Cratering is common in coatings that are ___ or ___ ___ by an inexperienced applicator.
Roller or Brush applied.
28
Air in the coating, sometimes caused by Brush/Roller application or improper mixing procedures can cause?
Cratering.
29
Cratering is also known as?
Vacuoles and pinholing.
30
Exposure to UV or other radiation sources can cause a coating to?
Chalking
31
These are caused by air trapped in a coating during mixing which creates a foam or bubbly surface on the liquid coating.
Air Voids
32
While initially invisible, Air voids generally lead to a coating failure in the?
Near future.
33
Air voids are pockets of air trapped inside the coating film during ___ and creates a foam or bubbly surface n the coating.
Mixing.
34
When a mixer is run too fast air can become trapped in the coating causing?
Air Voids.
35
(According to Photo) Air voids look just like foam.
Just a note.
36
Pinholes are very small holes in a coating caused by painting over an 1___ ___ ___ or ___ ___ ___.
2. ___ or ___ escaping through a porous film cause these tiny holes.
3. Zinc coatings ___ ___ so quickly that these holes will not fill back in.
1. Inorganic Zinc Coating or sprayed metal coatings.
2. Air or solven.
3. Sets up.
37
Pinholes are easy to avoid by simply using a ___ ___ followed by a ___ ___.
Mist coat followed by a full coat.
38
The repairs for 1____, ___, and ___ are very difficult since the hole generally reforms in any coating applied over them. The only sure fix is 2___ ___ to ___ ___.
1. Pinholing, Cratering, and Vacuoles.
| 2. Sanding down to bare metal.
39
The repairs for 1____, ___, and ___ are very difficult since the hole generally reforms in any coating applied over them. The only sure fix is 2___ ___ to ___ ___.
1. Pinholing, Cratering, and Vacuoles.
| 2. Sanding down to bare metal.
40
(According to Photo) Pinholes like tiny needle holes in the coating.
Just a note.
41
Discoloration/staining:
Rust stains are not normally a problem, except as a matter of 1___.
If necessary, clean by 2___, and ___ ___.
The only way to stop this from occurring is to ___ or ___ the item that is rusting or bleeding onto the coating.
1. Aesthetics.
2. Sanding and over coating.
3. Repair or replace.
42
This defect is caused by the application of IOZ or sprayed metallic paint?
Pinholes.
43
Heat related damage can occur during any project because it is common for someone to 1___ ___ ___ ___.
2. This repair should, just like any other repair follow the ___ or ____ ___.
1. Weld over new paint.
| 2. Specification or Manufacturers recommendations
44
Blistering are dome, or circular shaped, projections of the coating film held 1___ from the ___. (Raised.)
1. Away from the substrate.
45
Blisters can have 1____ ___ depending on the cause. The basic cause is a loss of 2___ in localized areas.
1. Irregular shapes.
| 2. Adhesion.
46
These may be filled with water, solvent, caustic, gas, oxygen, crystals, or rust.
Blisters.
47
Blisters can have any ___ or ___.
Size or distribution.
48
Blisters are evaluated by?
ASTM D 714,
Standard test method for evaluating degree of blistering of paints.
49
The Standard test method for evaluating degree of blistering of paints is?
ASTM D 714
50
Blisters can be caused by numerous factors.
1. Expanding ___ or ___ ___ can be caused by ___ ___ in the film, possibly due to ___ ___, or excessive ___ surface drying the coating.
Expanding water or vapor can be caused by entrapped solvents in the film possibly due to high humidity, or excessive wind surface drying the coating.
51
Excessive film thickness may also be the cause of blistering. In atmospheric service other causes of blistering include ___ over a ___ ___. (Water)
Coating over a contaminated surface.
52
The oil/grease/silicone are reasons for?
Blistering/fish eyes.
53
In atmospheric service, blisters may be caused by coating over ___, ___, ___, ___, ___, ___ ___ or by ___ ___.
```
Oil
Grease
Moisture
Dirt
Dust
Soluble pigments or by Retained solvents.
```
54
Coating over these contaminants in an atmospheric service environment can cause?
```
Oil
Grease
Moisture
Dirt
Dust
Soluble pigments
Retained solvents.
```
Blistering.
55
In immersion or buried service blistering can be caused by 1___ ___ due to:
]2. An overactive ___ ___ system.
3. Stray ___.
4. ___ caused by trapped soluble salts.
1. Electro-endosmosis
]2. An overactive cathodic protection system.
3. Stray currents.
4. Osmosis caused by trapped soluble salts.
56
Do not ___ blisters unless it is to test them or their contents to determine cause.
Break.
57
Blisters may ___ the surface.
Protect.
58
The only reasonable repair for blisters, if repair is necessary, is to:
1. ___ the coating.
2. ___ the area.
3. ___ whatever caused the blistering.
4. ___ the coating system.
1. Remove the coating.
2. Clean the area.
3. Fix whatever caused the blistering.
4. Replace the coating system.
59
Cracking and detachment defects are visible cracks in a coating that may either penetrate a ___ ___ of coating or the ___ ___ ___.
Single layer of a coating or the entire coating system.
60
The main cause of Cracking and Detachment is ___ ___ due to 2___ in the ___ or 3___ ___ in the coating as it ages.
1. Stress related.
2. Movement in the substrate.
3. Internal stress.
61
Causes of Cracking and Detachment are:
1. ___ Stress
2. ___ ___.
3. ___ ___ that are applied too heavily.
4. ___ and ___ of moisture.
5. ___
An example is 6___ cracking which is seen when the ship comes out of the water for inspection/work.
1. Substrate Stress
2. Internal Stress.
3. Chemically cured that are applied too heavily.
4. Absorption and deabsorption of moisture.
5. Aging
6. Antifouling
62
Once a coating has Cracked:
Remove and replace it. Preferably with a more flexible coating.
63
(According to Photo) Checking looks like a dry lake bed.
Just a note.
64
Repair of Checked coatings:
Remove and replace with proper coating material.
65
Repair of Checked coatings:
Remove and replace with proper coating material.
66
Checking appears as line cracks in the coating surface. Normally this appears only on the 1___ ___ and the cracks rarely go to the 2___.
1. Topcoat.
| 2. Substrate
67
Sometimes, magnification is needed to see?
Checking
68
The fundamental cause of Checking is?
Stress in the coating.
69
The fundamental cause of Checking is stress in the coating sometimes caused by 1___ ___ (a manufacturers issue) or a poorly written specification that requires a coating that is not meant for the 2 ____ or is incompatible with the 3 ___ ___.
1. Incorrect formulation.
2. Service
3. Underlying coating.
70
Alligatoring occurs where a 1___, ___ coating is applied over a 2___ ___ coating.
1. Hard, tough coating.
| 2. Softer, extensible coating.
71
Alligatoring can be caused when coating is exposed to ___.
Sunlight.
72
Coatings that cure by 1____ ____ may alligator if the coating is 2___.
(i.e. The surface cures 3___ relative to the ___ coating.
1. Oxidization-polymerization.
2. Heated.
(i.e. The surface cures rapidly relative to the underlying coating.
73
Alligatoring can be caused by:
1. A ___ coating applied to a ___ coating or substrate.
2. ___ ___ coatings that are ___.
3. Thickly applied coatings can Alligator when exposed to ___.
1. A hard coating applied to a softer coating or substrate.
2. Oxidization Polymerization coatings that are heated.
3. Thickly applied coatings can Alligator when exposed to sunlight.
74
Adhesion failures: Flaking, Delamination, Detatchment, and Peeling.
These defects are due to a 1___ of ___ between coating layers or the substrate caused by:
2. Coating applied to a ___ surface.
3. Wrong ___ ___ specified.
4. Failure to inspect ___ ___.
5. Insufficient ___ ___.
6. Exceeding the ___ ___ ___.
7. Application of ___ ___. (Alkyd over IOZ)
8. Applying a coating to a ___ ___.
1. Loss of adhesion.
2. Coating applied to a contaminated surface.
3. Wrong surface prep specified.
4. Failure to inspect surface pep.
5. Insufficient surface profile.
6. Exceeding the top coat window.
7. Application of incompatible coatings. (Alkyd over IOZ)
8. Applying a coating to a glossy surface.
75
Adhesion failures: Flaking, Delamination, Detatchment, and Peeling.
The repair depends on the extent of the 1___,
2. For smaller areas?
3. For larger areas?
1. Failure.
2. Remove, clean, feather edges, and replace coating.
3. Completely remove entire coating system and replace.
76
Failure on welds and edges:
Unless addressed by using a 1___ ___, a common source of in-service coating failure is rust that starts at a 2___ ___ or 3___ or ___ ___ ___.
1. Stripe Coat.
2. Sharp Edge.
3. Rough or spattered well seam.
77
The fundamental reason for Failure on welds and edges:
Coatings pull away from the 1. ___ __, and industrial coating application using 2___ or ___ can cause the coating to 3___ ___ small depressions in the substrate.
1. Sharp Edges.
2. Roller or Brush
3. Bridge Over
78
Failure on welds and edges repair:
1. Grind or round edges to at least a ___ radius. Unfortunately, this is not required by many specifications. When that is the case, the coating inspector 2___ require 3___ ___.
1. 0.078 in
2. Cannot
3. Stripe coating.
79
The addition of a stripe coat adds additional material on the 1___, with the goal of having a coating system with the safe DFT on the 1___ as on the 2___ ___.
1. Edge(s)
| 2. Flat surfaces
80
The International Maritime Organization (IMO) performance standard for protective coatings requires rounded edges to a 1___ radius or perming a 2___ ___ ___.
1. 0.078
| 2. Three pass grinding.
81
There are special DFT gauges that measure DFT on 1___. Typical gauges will not accurately measure closer the 2___ from an edge.
1. Edges.
| 2. One Inch.
82
Welder should 1___ welds and remove ___ ___ to the extent called for in the specification. However, what is acceptable for a weld may not be 2___ ___ a ___.
Coat rough welds with a 3___ to work coating into the roughness.
Weld spatter should be removed by 4___ or it will cause coating failure.
1. Dress welds and remove weld spatter.
2. Good for a coating.
3. Brush.
4. Grinding.
83
Coating does not encapsulate ___ ___ nor does abrasive blasting remove it.
Weld Spatter.
84
Rough welds should be coated with a ___ to work coating into the roughness.
Brush.
85
Weld spatter is removed by?
Grinding.
86
Another issue with welds and cut edges of steel is the 1___ from certain types of welding can 2___ the steel surface for a short distance around the weld.
1. Heat.
| 2. Harden.
87
Steel hardened by welding may not receive the same 1___ ___ as surrounding steel. CI's should always check 1___ ___ dept near any area that may be been subjected to heat from welding, or 2___ prior to 3___ ___.
1. Surface Profile.
2. Cutting.
3. Abrasive blasting.
88
Flame cut edges need to be ___ ___ before abrasive blasting.
Ground down.
89
Gouges or Chipped Spots are generally caused by accidental ___ or ___ on the job site.
Abrasions or impacts
90
No matter how careful a contractor is, ___ inevitably occurs on a coating project and it must be addressed.
Damage.
91
Gouges or Chipped Spots normally go through to the?
Substrate.
92
Even a small chip or gouge can start an 1___ ____ ___ causing a 2___ to form.
1. Active corrosion cell.
| 2. Pit
93
Gouges or chipped spots should be repaired by:
1. ___ ___ damaged areas to the ___ ___.
2. ___ the surrounding coating.
3. Ensure the repairs exactly replicate all ___ of the ___ ___ ___.
4. Precisely follow the ____, ___, and ___ ___ used for the undamaged portions of the coating system.
1. Sand down damaged areas to the bare substrate.
2. Feather the surrounding coating.
3. Ensure the repairs exactly replicate all coats of the original coating system.
4. Precisely follow the Specification, curing and environmental requirements used for the undamaged portions of the coating system.
94
Cissing is also knows as?
Fisheyes or crawling.
95
Cissing is the term for surface breaks in the film that ___ ___ ___.
Reveal the substrate.
96
Cissing is often a result of ___ or ___ contamination on the substrate.
Oil or grease.
97
The fundamental reason to have a CI on a job site is to avoid 1___. However, since most jobs cannot be inspected 100 percent of the time over 100 percent of the surface, ___ ___ coating failures do occur. Inspectors who are diligent and who closely observe work at critical times reduce, if not eliminate, premature coating failures.
Application related.
98
These terms describe a surface break in the film that reveal the substrate. They are often a result of grease or oil contamination.
Cissing (aka fisheyes or crawling)
99
This is the result of air released from the surface of the coating at the point where the coating is partially cured and the coating does not flow back to cover the void created by the air release.
Cratering.
